Various types of thermal heads have been proposed to date as printing devices for use in facsimiles, video printers, or the like. For example, there is known a thermal head comprising: a substrate; an electrode disposed on the substrate; an electric resistor connected to the electrode, part of which serves as a heat-generating section; and a protective layer disposed on the electrode, as well as on the heat-generating section (refer to Patent Literature 1, for example). In Patent Literature 1, there is described a protective layer obtained by disposing a first layer made of SiO2 on the electrode and the heat-generating section, and then disposing a second layer made of Ta2O5 on the first layer.